Maybe the Obama Adminstration's apparent abandoning of missile defense installations in Eastern Europe can signal a new way of thinking about national security, instead of relying on the old thinking.
Expect the usual shrieking from the wingnut gallery. No one could ever conclusively argue why these bases were a good idea; they were supposed to deter Russia, but at the same time weren't aimed at Russia, and couldn't possibly have stopped a Russian attack. They were supposed to defend from Iranian missiles, even though no one could ever figure out a plausible reason why Iran would fire ballistic missiles at Europe. Eastern European missile defense was, in short, insane; it was conceived by missile defense fanatics in the United States, and abetted by policymakers in Poland and the Czech Republic who wanted a clear signal of US commitment to their defense. The latter motivation was defensible; the former not so much.
We cannot just be the world's protector; heck, with our desiccated financial state, we can hardly be our own protector anymore. A more balanced multilateralism will reduce our military commitment globally and promote a more lasting peace. Bugging out of useless missile defense sites in Europe could lead to bugging out of, I don't know, the military outposts in 130 nations throughout the world.
Now, if we can apply this to Afghanistan, and actually think critically about the task at hand and how best to reach it, we may have something. Although, it appears the commanders will ask for another slow and steady escalation of 20,000 more troops. We have to break out of this kind of thinking.